Field
This disclosure relates generally to semiconductor devices, and more specifically, to semiconductor devices attached to exposed pads.
Related Art
Some types of packaged semiconductor devices include a semiconductor die mounted on a lead frame. Lead frames, which include an exposed pad for attachment of the semiconductor die, are commonly manufactured by etching, stamping, and punching preformed sheets of metal such as copper, copper alloys, and iron-nickel alloys into desired shapes. A common problem in attaching the semiconductor die to the exposed pad is delamination. Another problem is that the material, commonly referenced as die attach, used to attach the semiconductor die to the exposed pad may crack and delaminate at the adjoining interfaces of the die attach. These problems have generally been approached by optimizing the materials, materials' thicknesses, and the conditions, such as temperature, under which the materials are attached. Although the problems have been reduced, they have not been completely solved, especially under all conditions.
Accordingly, there is a need for a further improvement in addressing one or more of the problems noted above regarding the attachment of a semiconductor die to an exposed pad.